Colour coding's initial test (5)
I believe the answer is:
coral
'colour' is the definition.
(I know that coral is a type of pink)
'coding's initial test' is the wordplay.
'initial' indicates taking the first letters.
'test' becomes 'oral' (oral is a type of examination).
The initial letter of 'codings' is 'c'.
'c'+'oral'='CORAL'
(Other definitions for coral that I've seen before include "Reef-forming sea life" , "Hard pink substance formed by skeletons of tiny sea creatures" , "Hard substance on the seabed" , "Marine substance, often forming reefs" , "Shakespeare: 'Full fathom five thy father lies, of his bones are . . . . . made'" .)